Studying at Westhoughton High School, she went onto take A-Levels at Canon Slade School. Aged thirteen, she joined the Octagon Youth Theatre before a period at the youth theatre of the Royal Exchange, Manchester, although Peake's early attempts to enter the acting profession were unsuccessful. Aged twenty-one, she obtained a place at the Royal Academy of Dramatic Art - her attempts to find sponsorship for RADA were the subject of a 1996 documentary by the South Bank Show. Eventually, after being put forward by RADA, she was awarded the Patricia Rothermere Scholarship.

Other TV and film credits include roles in Hetty Wainthropp Investigates, Girls' Night, Picking up the Pieces, Sunburn, Jonathan Creek, Clocking Off, Dinnerladies, The Way We Live Now, Linda Green, Holby City, Dalziel and Pascoe, At Home with the Braithwaites, Christmas Lights, Frozen, Shameless, The Devil's Whore, Little Dorrit, Criminal Justice, Silk, The Hollow Crown and Room at the Top.